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Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
Crecimiento unimodal vivo de vesículas complejas de poliion a través de la polimerización supramolecular
Yasutaka Anraku1, Akihiro Kishimura, Yuichi Yamasaki
1Department of Materials Engineering, Graduate School of Engineering, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656, Japan.
Journal of the American Chemical Society
|January 8, 2013
Resumen
Investigadores demuestran una nueva polimerización viva supramolecular bidimensional usando complejos de poliion (PICs). Este sistema permite el crecimiento controlado de vesículas PIC monodispersas (nano-PICsomes) que pueden ser reiniciadas, ofreciendo nuevas posibilidades en la ciencia de los materiales.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Controlar los autoensamblajes moleculares de mayor dimensión es un desafío.
- Pocos sistemas exhiben polimerización supramolecular en dimensiones más altas.
Objetivo del estudio:
- Para investigar el comportamiento de autoensamblaje de los complejos de poliion (PIC).
- Para demostrar un sistema de polimerización viviente supramolecular bidimensional.
Principales métodos:
- Se utilizan copolímeros de bloque de poli (etilenglicol) -polielectrolito para formar PIC.
- Caracterizó la autoensamblaje y la dinámica de crecimiento de las vesículas PIC (nano-PICsomas).
- Investigó la respuesta de nano-PICsomes a la tensión mecánica y la adición de PICs de la unidad.
Principales resultados:
- Se obtienen vesículas PIC unilamelares monodispersas y submicrométricas (nano-PICsomas).
- Crecimiento demostrado dependiente del tiempo de nano-PICsomes con distribución de tamaño y estructura mantenidos.
- Se demostró que el crecimiento de las vesículas se produce a través del consumo de PICs de la unidad (uPICs) y se puede reiniciar.
- Se observó la disociación de nano-PICs en uPICs bajo estrés mecánico.
Conclusiones:
- El sistema representa una polimerización viviente supramolecular bidimensional de uPICs.
- Esto proporciona un nuevo método para la síntesis controlada de autoensamblajes de mayor dimensión.
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